Truing tool for watch balance wheels



Jan. 25,1938; w. PODGURSKI TRUING TOOL FOR WATCH BALANCE WHEELS Filed Sept. 3, 1936 INVENTOR ATTORNEY.

III

Patented Jan. 25, 1938 UNITED STATES PATENT OFFICE. r

TRUING TOOL FOR WATCH BALANCE WHEELS 6 Claims.

This invention relates to devices used by watchmakers for truing balance wheels and has as its main object the provision of means whereby the rim of a balance or like wheel may be accurately adjusted to rotate concentrically upon its axis.

A further feature is in the provision of means whereby the pins, set in the rim of the wheel, may be calibrated with respect to their length and registration.

Another purpose is to produce a tool capable of minute adjustment in conformity with the proportions of the wheel undergoing operations.

These and other advantageous objects, such as compactness, convenience in operation and moderate cost, are accomplished by the novel construction, combination and arrangement of parts hereinafter described and illustrated in the accompanying drawing constituting an essential component of this disclosure, and. in which:-'

00 Figure 1 is a side elevational View of an embodiment of the invention, partially in section.

Figure 2 is a similar view of the opposite side.

Figure 3 is an edge view of the same.

Figure 4 is an enlarged sectional view taken on line 44 of Figure 1.

Figure 5 is a transverse sectional view taken on line 5-5 of Figure 4.

Referring to the drawing in greater detail, the device will be seen to consist of a tool having duplicate jaws at each end.

The body of the tool is composed of two equal portions l5l6, substantially alike, in one of which, as l5, are firmly secured two spaced guide rods I1 arranged in parallel and slidable in corresponding openings IS in the mating member.

Midway between the rods the elements l5|6 are formed concavely to provide space for a knurled circular head 20 from each side of which extend screws 2 I 22, threaded respectively right and left hand into the elements lS-IE and by which the two sides of the implement may be forcibly moved towards or from each other.

Extending from the end portions of the elements l5-l6 are jaws 23-24, inwardly bowed at their outer ends, in which are fixed opposed, aligned terminals 25-46 having fine sockets in their proximate ends adapted to receive the pointed ends of wheel staffs reaching equally outward from the hub of the balance wheels to be 60 trued.

It will now be obvious that by proper manipulation of the member 20, the wheels can be held rotatively between the jaws.

A bar 311, having a thickened lug 3! at one end,

55 is held slidable across the jaws 2324 by clips 3?.33 and is adjustable within them by a screw 34 threaded into the lug 3i and provided with a knurled operating head 35.

The inner end 35 of the screw is'rctatable in an opening 31 in the jaw 23 and provided with a fixed collar 38. A set screw 39, in the. jaw 23 provides means to clamp the screwwhen in its adjusted position. See Fig. 4.

A similar but larger set screw id, in the jaw 24, may be used to clamp the bar 30 against the clip While clips 33 are permanently fixed, clips 32 and M can be opened or closed in latch fashion. Clips 32 and 5! may thus beturned on a pivot screw on one end of each clip and locked tight by a corresponding screw at the opposite end of each clip, thereby. permitting a quickchange oi the bar 30 from. one end of the toolto the other.

An elongated slot 46 in the bar 30 permitsin connection with a clamping nut 4'! longitudinal adjustment of a slide 56 transversely of the jaws.

In this slide 50 operates a screw 5| having an operating head 52 by which a sleeve 53 with an inside thread may be moved towards or from the plane of the balance wheel, this sleeve having fixed in its outer end a rod 54 turned angularly at its end to constitute a feeler 55, the sleeve being flattened on one side to prevent turning, as shown at 56, Fig. 4.

From the foregoing it will be apparent that the feeler 55 may be moved longitudinally along the bar 30, clamped to it by the screw 41 and then finely adjusted by the head 35 which moves the bar; also that the feeler may be finely adjusted, relative to the axis of the wheel being trued by the screw 52.

It is further apparent that the bar 30 and its appurtenances may be moved bodily to the other end, of the instrument at will.

As many changes of construction could be made within the scope of the invention, it is to be understood that all matter contained in the foregoing description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

Having thus described the invention, what is claimed as new and desired to secure by Letters Patent, is:

1. In a balance wheel truing tool comprising two jaws adjustable toward and away from each other and provided with bearings for the ends of a wheel staff: a slotted bar, slidably mounted for movement independently of and across said jaws, a screw adjustment to minutely control said movement, clamping means to fixedly hold said bar in an adjusted position, a slide adapted for movement within the slot in said bar, a feeler adjustably mounted within said slide and adapted for movement at right angles to said slot, and means to fixedly hold the slide and the bar in place after adjustment in both directions.

2. In a balance wheel truing tool comprising two jaws adjustable toward and away from each other and provided with bearings for the ends of a wheel staff: a slotted bar, slidably mounted for movement independently of and across said jaws, a screw adjustment to minutely control said movement, clamping means to fixedly hold said bar in an adjusted position, a slide adapted for movement within the slot in said bar, a feeler comprising a laterally bent tip and a straight shank, the latter being adjustably mounted within said slide and adapted for movement at right angles to said slot, and means to fixedly hold the slide and the bar in place after adjustment in both directions.

3. In a balance wheel truing tool comprising two jaws adjustable toward and away from each other and provided with bearings for the ends of a wheel staff: a slotted bar removably latched in position on said jaws and slidably mounted for movement independently of and across said jaws, a screw adjustment to minutely control said movement, clamping means to fixedly hold said bar in an adjusted position, a slide adapted for movement within the slot in said bar, a feeler adjustably mounted within said slide and adapted for movement at right angles to said slot, and means to fixedly hold the slide and the bar in place after adjustment in both directions.

4. In a balance wheel truing tool comprising two jaws adjustable toward and away from each other and provided with bearings for the ends of a wheel stafi: a slotted bar removably latched in position on said jaws and slidably mounted for movement independently of and across said jaws, a screw adjustment to minutely control said movement, clamping means to fixedly hold said bar in an adjusted position, a slide adapted for movement within the slot in said bar, a feeler comprising a laterally bent tip and a straight shank, the latter being adjustably mounted within said slide and adapted for movement at right angles to said slot, and means to fixedly hold the slide and the bar in place after adjustment in both directions.

5. In a balance wheel truing tool comprising two jaws adjustable toward and away from each other and provided with bearings for the ends or" a wheel staff: a slotted bar removably latched in position on said jaws and slidably mounted for movement independently of and across said jaws, a screw adjustment to minutely control said movement, clamping means to fixedly hold said bar in an adjusted position, a slide adapted for movement within the slot in said bar, a feeler adjustably mounted within said slide and adapted for movement at right angles to said slot, and means to fixedly hold the slide and the bar in place after adjustment in both directions substantially as described.

6. In a balance wheel truing tool comprising two jaws adjustable toward and away from each other and provided with bearings for the ends of a wheel staff: a slotted bar removably latched in position on said jaws and slidably mounted for movement independently of and across said jaws, a screw adjustment to minutely control said movement, clamping means to fixedly hold said bar in an adjusted position, a slide adapted for movement within the slot in said bar, a feeler comprising a laterally bent tip and a straight shank, the latter being adjustably mounted within said slide and adapted for movement at right angles to said slot, and means to fixedly hold the slide and. the bar in place after adjustment in both directions substantially as described.

WALTER PODGURSKI. 

